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how do you filter pandas dataframes by multiple columns
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hi it's a single key, just a word, that would correspond to the gender (male, or female) or year (13, 14) Didn't know you could have a tuple of keys. Could you share an example of when and how you would do this?
– yoshiserry
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What is the JavaScript >>> operator and how do you use it?
...0 >>>0 === 0 evaluates as true? even though lemons is obviously a word..?
– Zze
Mar 27 '18 at 23:03
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Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
...e same cost because they have to be validated against the schema. In other words this is a complete wash.
For item 4, when you specify specific columns, your query plan cache could get larger but only if you are dealing with different sets of columns (which is not what you've specified). In this ca...
How to add an extra source directory for maven to compile and include in the build jar?
...c/bootstrap directory that I want to include in my build process, in other words, I want maven to compile and include the sources there in my build. How!?
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Which equals operator (== vs ===) should be used in JavaScript comparisons?
...f Type(constructor) is not Object, throw a TypeError exception.
With other words, if String wouldn't be of type Object it couldn't be used with the new operator.
new always returns an Object, even for String constructors, too. And alas! The value semantics for strings (see step 11) is lost.
And thi...
c++11 Return value optimization or move? [duplicate]
...: Sounds like a bug in the documentation, specifically, it sounds like the wording of the documentation wasn't updated for C++11. File a bug? @JonathanWakely?
– Kerrek SB
Apr 21 at 14:08
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`from … import` vs `import .` [duplicate]
... have a name starting with _) or whatever name
you mentioned.
Or, in other words, after you've run this statement, you can simply
use a plain (unqualified) name to refer to things defined in module X.
But X itself is not defined, so X.name doesn't work. And if name
was already defined, it is replace...
How to think in data stores instead of databases?
...provides a better feature much LIKE(Oh no! datastore does not have LIKE Keyword) SQL which is GQL.
Data Insert/Update/Delete/Select
This where we all are interested in, as in RDMBS we require one query for Insert, Update, Delete and Select just like RDBMS, Datastore has put, delete, get(dont get to...
Are email addresses case sensitive?
...g email systems that support such nonsense.
p.s. ILIKE is a PostgreSQL keyword: http://www.postgresql.org/docs/9.2/static/functions-matching.html
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Struct like objects in Java
...here the class is essentially a data structure, with no behavior. In other words, if you would have used a struct instead of a class (if Java supported struct), then it's appropriate to make the class's instance variables public.
http://www.oracle.com/technetwork/java/javase/documentation/codeconve...